The Sydney rental market is heavily tipped in favour of landlords, with vacancies reaching a critical low in the last month.
Data from the Real Estate Institute of New South Wales (REINSW) shows housing availability fell by 0.3 per cent in March.
The number of untenanted rentals is currently sitting at 1.4 per cent.
REINSW president Malcolm Gunning said availability was verging on "crisis levels".
“We haven’t seen vacancy rates right across Sydney this low since November 2011,” he said.
“Sydney is going backwards in regards to properties available for rent.”
The inner city saw rates fall by 0.2 per cent to a low of 1.3 per cent overall.
Vacancies in the middle suburbs declined by 0.4 per cent to a final rate of 1.6 per cent.
In the outer suburbs, meanwhile, vacancies remained more stable, with a drop of only 0.1 per cent for a rate of 1.5 per cent.
On the other hand, major regional centres saw a slight climb in available properties.
Wollongong climbed by 0.7 per cent, for a final rate of 2.3 per cent. Newcastle saw a more moderate rise of 0.1 per cent to 2.5 per cent.